Cutting-tool.



' Patented July 4, I899. H. S. NEWCOMB.

CUTTING TOOL.

(Application filed Apr. 15, 1899,

(No Model.)

UNITED STATES HERBERT S. NEWVCOMB, OF

P TENT OFFICE.

MALDEN, MASSACHUSETTS.

CUTTING-TOOL.

SPECIFICATION forming part of Letters Patent No. 628,280, dated July 4, 1899.

Application filed April 1 5,1 899.

To all wlumt it may concern:

Be it known that I, HERBERT S. NEWCOMB, of Maiden, county of Middlesex, State of Massach usetts, have invented an Improvement in Cutting-Tools, of which the following description, in connection with the accompanying drawings, is a specification, like letters and figures on the drawings representing like parts.

This invention has for its object the production of a strong and durable cutting-tool at a-low cost, my invention being particularly adapted for hewing-axes and the like.

In accordance with my invention the body portion of the tool is made of cheaper metal, such as malleable cast-iron, and the steel blade is made detachable therefrom, novel means being employed for securely and firmly looking the blade and body portion together, so that in use they will not work loose.

Figure l is a side elevation of a hewing-ax embodying my invention, the blade being shown in place. Fig. 2 is a perspective View showing the body portion and blade separated. Fig. 3 is an enlarged under side view, detached, of the locking member or key; and

-Fig. 4 is a transverse sectional view taken on the line m as, Fig. 1, looking toward the right hand.

I have herein shown my invention as embodied in a hewing-ax, which is one practical form oftool involving the invention, without, however, restricting myself strictly thereto.

Referring to Figs. 1 and 2, the main or body portion A of the tool is made, preferably, of malleable cast-iron of suitable or desired shape in general, the body being reduced in thickness at one end to form a fiat web a and leaving a shoulder or back-rest a, which is undercut, as shown at a Fig. 2. The shoulder or back-rest is made as a circular arc, extending from one to the opposite edge of the body portion, and midway between its ends a key-seat a is made, its sides 2 and 3 converging toward the back-rest a, which they intersect, so that the key-rest is open thereat. The depth of the seat is shown as equal to that of the back-rest, and the sides 2 and 3 are inwardly beveled, so that the seat is of greater area at its open top than at its bottom.

The removable bit or blade B is made of hardened and properlytempered steel, its fiat face resting on and being supported by Serial No. 713,149. (No modeLl the web a, while the back I) of the knife is made as a circular arc of the same degree of curvature as the backrest to fit snugly against the same, the blade-back having a projecting rib b to enter the undercut portion a of the back-rest.

Suitable screws or rivets s, Fig. 1, are passed through the holes b and a in the blade and body portion, respectively, to retain the blade on the web, the rib b acting to prevent any lateral separation of the blade and web.

Opposite the key-seat a in the body A a similar seat b is made in the blade, its beveled sides 5 6 converging toward and intersecting the blade-back, so that when the blade is in position on the body a double seat is made, the opening ends of the two seats registering the one with the other, the curved line of the joint between blade and body portion passing through the center of the double seat.

A key d (shown separately in Fig. 3) is provided to enter the double seat described, said key having V-shaped ends, the faces 8 10 of which are beveled from one to the other side of the key to correspond to the beveled sides of the seats. At its ends the key bears firmly against the beveled walls of the seats; but there is clearance (see Fig. 1) between the sides of the key-and the back walls of the seat, and, as shown in Fig. 4, the key does not bottom in the seats.

A screw-bolt d passes through a hole a in the body portion A and engages a threaded hole (1 in the key to hold the latter in place necessary.

It will be obvious that when a blow is struck by the edge of the blade the impact of such blow will be transferred to the body portion through the shoulder or back-rest a, and unless some means is provided for preventing fastenings s between the blade and body. By making the back of the blade and the back-rest circularly curved, however, I provide for a sliding tendency of the blade whenever struck at one or the other side of the center of its edge, and by means of the key the tendency of such blows is to more firmly secure body and blade together.

Suppose that the upper part of the bladeedge is struck, (viewing Fig. 1). Then the and also serving to set the latter up when it these constant impacts will soon loosen the tendency of the blade is to move in the direction of arrow 20; but the wall (3 of the seat if then actsupon the adjacentend wallof the key, and it in turn acts, by the beveled faces 8 10 of its other end, to cramp or draw the blade toward the body portion, and at the same time the face of the upper end of the key in Fig. 1 acts on the face 2 of the seat a to at that part draw the body and blade together. This action takes place time after time, and as a result the continued use of the tool only serves to draw body and blade more firmly together.

When the blade becomes worn out, it can be removed readily after loosening the key and a new blade substituted.

My invention is not restricted to the precise construct-ion and arrangement shown, as the same may be modified or varied without departing from the spirit and scope of my invention.

Having described my invention, what I claim, and desire to secure by Letters Patent, 1s

1. Atoolcomprisingabodyportion reduced at onc'end to form a web and having an adjacent circularly-curved back-rest, a detachable blade supported laterally by said web and having its back curved similarly to the backrest, and a removable key to simultaneously engage said body portion and blade at the junction of theireurved portions and between the ends of the latterand lock them together.

2. Atool comprisingabodyportion reduced at one end to form a web and having an adjaccnt circularly-curved back-rest, a detachable blade supported laterally by said web and having its back curved similarly to the back-rest, one or more connections between the blade and web, and an independent key to simultaneously engage the body portion and blade midway between the ends of their curved portions and lock them together.

3. A tool comprising a body portion reduced at one end to form a web and having an adjacent circularly-curved back-rest, a detachable blade supported laterally by said web and having its back curved similarly to the back-rest, bevel-ended and coactin g key-seats in said body portion and blade respectively midway between the ends of the curved portions thereof, and a removable key to enter said seats simultaneously and lock the blade to the body portion.

1-. A tool comprising a body portion reduced at one end to form a web and having an adjacent circularly-curved and undercut backrest, a detachable blade supported laterally by said web and having its back similarly curved and provided with a rib to enter the undercut portion of the back-rest, akey-seat in the body portion and blade, respectively, each-having converging, beveled ends, and a key having V-shapcd ends also beveled, to enter said seats simultaneously and thereby lock the blade to the body portion.

5. A tool eomprising'a body portion provided with a circularly-curved back-rest, a removable blade having a similarly-shaped back, oppositely-located key-seats, in the body portion and blade, respectively, each having converging, beveled ends, a key having beveled,V-shaped ends, to enter the seats simultaneously and lock the blade to the body portion and means to draw the keyinto the seats.

6. A tool comprising a body portion provided with a circularly-curved back-rest, a removable blade having a similarly-shaped back,oppositely-located key -seats,in the body portion and blade, respectively, each having converging, beveled ends, a key having beveled,V-shaped ends, to enter the seats simultaneously, and of less thickness than the depth of the latter, and means to retain the key firmly seated.

7. An ax comprising a body portion terminating in a web and an undercut, circularly-curved back-rest or abutment, adetaehable blade adapted to be supported by said web and having its back shaped to fit the back-rest, opposed key-seats in the body and blade having inwardly-beveled end walls, a key having V-shaped, beveled ends to enter said seats simultaneously, means to draw the key into the seats, and independent connections between the blade and the web.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

HERBERT S. NEWCOMB.

Witnesses:

AUGUSTA E. DEAN, FREDERICK L. EMERY. 

